1. Field of the Invention
The present invention relates to a communication apparatus that makes a wireless communication by a communication method, and particularly to a communication apparatus that can maintain an excellent communication quality in a wireless communication even when the wireless communication is subjected to interference by an external radio wave.
2. Description of Related Art
There are known communication apparatuses capable of wirelessly communicating information or data by various methods that use respective frequency bands, which in some cases overlap with one another.
When such overlapping of the frequency bands used in the wireless communications made by the communication apparatuses occurs, the wireless communications interfere with one another, inviting an increase in a transfer error rate of each wireless communication. In particular, when the transfer error rate is thus increased in a communication made by a communication apparatus that wirelessly communicates audio data, such as digital cordless telephone and radio communication equipment, there arises a problem that the audio quality deteriorates.
To deal with the problem, JP-A-6-224837 (see paragraph [0012] of JP-A-6-224837) proposes a mobile wireless telephone system in which a transmitting unit sends same audio data repeatedly a plurality of times, and a receiving unit selects a non-erroneous one of a received plurality of pieces of the same audio data, and converts the selected piece of the audio data into an audio signal, which is outputted or played.
The mobile wireless telephone system can decrease the transfer error rate and accordingly maintain an excellent communication or audio quality. However, the receiving unit should repeatedly implement a same reception processing for all the pieces of the audio data, consuming a lot of electricity.
In view of this, JP-A-11-341534 (see paragraph [0019] of JP-A-11-341534) proposes a paging receiver that receives information in units of subframes and detects an error in received information subframe by subframe. When any error is not found or detected in a subframe, the subframe is received. The subframe reception of which is thus complete will not be received again. More specifically, when the “self-frame” is received by the paging receiver the next and following times, a processing of receiving the subframe is not implemented, thereby reducing the power consumption.
However, the paging receiver should implement a processing of detecting an error for every subframe, thereby making the processing in the paging receiver to receive information relatively complex as a whole.